Spark arrester and exhaust silencer



Get. 24, 1950 V F. E. BECKETT ,5

SPARK ARRESTER AND EXHAUST SILENCER Filed May 29, 1946 4 B INVENTOR.

FARLEY E. BECKETT AT TORNE Y Patented a. 24, 1950 SPARK ARRESTER AND EXHAUST SILENCER Farley E. Beckett, Azusa, Calif. Application May 29, 1946, Serial No. 673,034

(Granted underthe act of March 3, 1883, as amended AprilBO, 1928; 370' O. G. 757) Claims.

This invention relates to exhaust arresting devices and more particularly to spark arrestors and exhaust silencers.

The silencing of exhausts from engines has been encountered with great frequency. When it is necessary also to remove sparks from such exhaust in order to reduce the fire hazard incident to industrial plants, locomotive, and other situations, the 'problem is seriously aggravated. Such problems were found to. be particularly aggravating aboard ship during wartime activity when it was necessary to eliminate all sparks that might reveal the presence. of the ship to the enemy. For this purpose, conventional spark arrestors were found to be unsatisfactory in that the same failed to provide positive removal of all sparks from the exhaust, were of such heavy construction as to raise the center of gravity of smaller vessels and reduce the permitted armament thereon, and created back pressures on the power units upon whose exhausts they were mounted thereby reducing the efficiency of said power units.

Objects of the present invention, therefore, are to provide an improved silencer and spark arrestor, of light construction and reliable performance; to provide an improved exhaust arresting device adapted to remove heavier material from exhaust vented therethrough; to pro vide improved centrifuge means for segregating vented material; to reduce back pressures on engines heretofore incident to spark arrestors and exhaust silencers; to remove sparks from exhaust material; to provide an exhaust silencer and spark arrestor'adapted to accommodate a plurality of exhaust sources; and to provide improved elements and arrangements thereof in a device of the character and for the purposes set forth.

In accomplishing these and other objects of the present invention, I have provided improved details of structure, the preferred form of which is illustrated in the accompanying drawing, wherein:

Fig. l is a horizontal, cross-sectional view of an exhaust arresting device embodying the features of the present invention, taken on the line of Fig. 2.

Fig. 2 is a view, partly in elevation and partly in section, taken on the line 2-2 of Fig. 1.

Fig. 3 is a detailed, sectional view, taken on line 3-3 of Fig. 1, showing bracket means for spacing and securing an inner member within the shell of the device.

Referring more in detail to the drawing:

The numeral I designates a housing or casing having a substantially cylindrical, hollow shell or body 2, an upper closure or top 3, and a lower closure or bottom 4 (Fig. 2). The housing I has access openings 5 provided in its shell 2 and an axial opening 6 in its bottom 4 (Fig. 2). Inspection or closure plates 1 and 8 engage in the access openings 5 and 5, respectively. The upper closure or top 3 is provided with an axial vent opening 9 which communicates with the hollow interior [0 of the housing.

Two or more exhaust ducts H, which communicate with sources of exhaust material (not shown) for conducting the exhaust therefrom into the interior ID of the housing, extend into said housing at substantially tangential or chordal directions to the shell thereof. It is pointed out that the ducts are preferably positioned so as to' have their discharge ends spaced at irregular unequal or different intervals to reduce sound resonance therebetween. When only two exhaust ducts are employed, as shown in the drawing, their discharge ends are non-diametrically opposed relative to the shell and each other. It is further observed that the ducts extend inwardly a distance sufficient to cause the exhaust gases to move in a centrifugal path to substantially reduce the back pressure on the incoming exhaust gases.

By extending the ducts H inwardly within the cylindrical wall of the housing I, the exhaust gases are caused to enter the housing interior H] in a direction closely approaching the path of the whirling gases therein at the position of entrance, which minimizes or reduces the back pressure exerted upon the incoming gases by the gases within said housing. Each duct is shown as projectin a substantial distance into the housing interior and preferably extends inwardly to a position adjacent a radial plane perpendicular to the axis of the duct.

An inner member or partition I2, having a substantially cylindrical lower portion or sleeve l3 and a funnel-shaped or frusto-oonical upper portion or hood I4, is mounted coaxially within the housing, such as by welding the sleeve within the opening 6 of the housing bottom 4. The provision of the inner member l2 forms an annular chamber A into which the ducts ll discharge theexhaust material.

The inner member preferably is of less height and its hood I4 is of less diameter than the housing interior [0, whereby the external periphery of said hood is spaced from the shell 2 and from the top 3. To maintain the inner member inthis position, a plurality of brackets l5 are welded or otherwise secured to the shell and hood as shown in Figs. 1 and 3. Y

An annular partition or plate It, having an ex- 'exhaust material.

ternal diameter slightly less than the diameter of the housing interior, is disposed radially within said interior concentrically of the sleeve 13 of the inner member l2 and is preferably welded or otherwise secured to said sleeve. The partition 16, in cooperation with the shell 2 and the housing bottom 4, forms a settling chamber B into which exhaust material may pass from the chamber A through a peripheral space or opening i! provided between said partition and body due to the smaller diameter of the former.

The settling chamber B is preferably vented by a plurality of small ducts [8 which project upwardly through the partition [6, chamber A and hood H2 and establish direct communication between said chamber and the opening 9. To provide additional strength, the ducts l8 are welded or otherwise secured to the partition and hood.

A cylindrical stack I9 is secured to the housing top in circumscribing relation to the opening 9. Depending internall of the opening is an annular ring or collar 26 which, in effect, forms a continuation of the stack 19 and which is provided with a plurality of ports or orifices 2| for permitting additional access to said opening. To divert exhaust material away from the opening and thus deflect sound waves therefrom, an annular, outwardly-flared flange or skirt 22 depends from the lower end of the collar 29 and surrounds the upper ends of the ducts l8.

As is most clearly shown in Fig. 3, an annular angle iron 23 is welded to and connects the body 2 and top 3 of the housing.

Operation The operation of a spark arrestor and exhaust silencer constructed as described is as follows:

Exhaust material to be vented is directed by the ducts ll substantially tangentially or in chordal directions into the chamber A of the housing 1 so as to cause centrifugal movement of said The resultant centrifuge effect causes the heavier exhaust material, such as embers to be thrown outwardly against the shell 2. Upon striking the shell, the embers and other exhaust material move in either of two directions. Inasmuch as most of the heavier material moves downwardly, that course will first be described.

The heavier material, upon striking the shell, travels downwardly through the space i! into the settling chamber B and collects therein. This material is removed periodically through the access openings 5. The gases that accompany the heavier material into the settling chamber pass upwardly through the ducts l8 into the vent opening 9 and then out the stack 18. This described egress, from the exhaust ducts ll into the centrifugally moving exhaust gases in the chamber A, then outwardl against the shell 2, down through the space [7, through said settling chamber, and upwardly through the ducts l8 to the vent opening and stack, is so circuitous as to greatly attenuate sound waves carried by said exhaust material.

The other path of egress is provided from the centrifugally moving gases in the chamber A through the constricted space or opening between the hood l4, shell 2 and top 3 of the housing. The exhaust material rising through this constricted opening is relatively light and carries a proportionately smaller quantity of embers or spark material. Upon passing through the constricted opening, the exhaust material moves inwardly toward the stack l9 and a small portion thereof passes through the orifices 2| into said stack and is discharged thereby. The greater proportion of this exhaust material is deflected by the collar 20 and flange 22 away from the stack. This deflection provides an additional opportunity for heavier material, such as embers, to precipitate and travel downwardly into the inner chamber and collect on the inspection plate 8. The heavier material precipitated at this stage is periodically removed through the access opening 6.

The lighter gaseous material, after being deflected as described, moves inwardly, passing between the ducts l8 and then upwardly tlnough the vent opening 9 and the stack [9. Attention is called to the fact that the aforesaid paths of egress not only provide further precipitation of heavier material from the exhaust gases, but in addition, attenuate sound waves by causing the gases to be deflected by the collar 20 and flange 22 and to pass between the ducts 18 before being discharged by the stack.

It is further pointed out that the several paths from the exhaust ducts ll to the stack l9 are of different lengths precluding the resonating of the small amount of sound finding its way through said paths.

By actual test, it has been found that the manner of introducing the exhaust gases into the housing provides a reduction of atmospheric back pressure on the incoming gases. It has been found also that the preferred embodiment of the present invention successfully eliminates sparks from the exhaust material of a plurality of engines and that the sounds coming therefrom are successfully and efiiciently muflied.

While I have shown but one embodiment of my invention, it is susceptible to modification without departing from the spirit of the invention. I do not wish, therefore, to be limited by the disclosures set forth, but only by the scope of the appended claims.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of an royalties thereon or therefor.

I claim;

1. A spark arrestor and exhaust silencer includig, a cylindrical hollow housing, the housing having a flat top and bottom, said housing having access openings, plates for closing the access openings, an inner member disposed concentrically within said housing, the member having an inverted frusto-conical upper portion and a de pending cylindrical lower portion, said member being of less height and diameter than said housing and. having its cylindrical portion secured to said housing bottom, brackets fastening the upper portion of said member to said housing in spaced relation thereto and to its top. an annular partition plate of less diameter than said housing mounted therein circumferentially of said member and in spaced relation to said housing and bottom so as to form a settling chamber, an exhaust stack mounted on said top and extending therethrough into said housing, the stack having a plurality of openings in its inner end portion so as to communicate with the interior of said housing, a plurality of ducts extending through the partition plate and the upper portion of said member for establishing direct communication between the settling chamber and said stack, an outwardly flared flange depending from the lower end portion of said stack to deflect gaseous flow and sound waves away from said stack, and a plurality of exhaust pipes extending into said housing between the upper portion of said member and said partition so as to impart centrifugal motion to the exhaust gases therein.

2. An exhaust arresting device including, a housing having a cylindrical hollow interior, a sleeve member disposed concentrically within the housing to form an annular chamber therein, the upper end of said member being flared into a funnel-like portion communicating with the upper end of the housing interior, an annular partition surrounding said member to form a settling chamber below said annular chamber, passage means at the external periphery of said partition communicating between said chambers, an exhaust stack communicating with said housing interior, means establishing direct communication between the settling chamber and stack, means for directing exhaust gases into said annular chamber substantially tangentially thereof so as to impart centrifugal motion to the gases, and depending means carried by the lower end of said stack for deflecting sound waves and gaseous flow.

3. An exhaust arresting device including, a housing, an annular chamber within the housing, means for discharging exhaust gases into the annular chamber substantially tangentially thereof so as to impart centrifugal motion to the gases, a settling chamber below said annular chamber and communicating therewith for receiving heavy exhaust particles, vent means communicating with the settling chamber, and means establishing communication between the upper portion of said annular chamber and the vent means.

4. In a device of the character described, a hollow substantially cylindrical housing, a vent stack communicating with the interior of the housing,

exhaust pipes extending into the housing member I substantially tangentially thereof, the pipes being positioned at unequal intervals, and a partition plate of less diameter than said housing secured radially therein in spaced relation to one end thereof so as to provide a settling chamber into which heavier particles thrown outwardly by centrifugal motion of the gases may settle.

5. A spark arrestor and exhaust silencer including, a housing having a substantially cylindrical hollow interior, an inner member, mounted concentrically within the hollow interior to form an annular chamber therein, means for conducting exhaust gases into the annular chamber in chordal directions thereto so as to impart cylindrical movement to the exhaust gases therein, a transverse partition mounted on the inner member and forming a settling chamber in communication with and below said annular chamber, and venting means in communication with said housing interior and settling chamber.

FARLEY E. BECKETT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Leadbetter Nov. 27, 1945 

